<template>
<div class="app-container">
  <h2 style="text-align: center;">发布新课程</h2>
    <el-steps :active="1" process-status="wait" align-center style="marginbottom: 40px;">
      <el-step title="填写课程基本信息"/>
         <el-step title="创建课程大纲"/>
            <el-step title="最终提交"/>
    </el-steps>

  <el-form label-width="120px">
    <el-form-item label="课程标题">
      <el-input v-model="courseInfo.title" placeholder=" "></el-input>
    </el-form-item>
  <!-- 所属分类 TODO -->
    <el-form-item label="课程类别">
      <el-select
        v-model="courseInfo.subjectParentId"
        placeholder="一级分类" @change="subjectLevelOneChanged" >
<!--      由于框架原因，value会自动被赋值id-->
        <el-option
          v-for="subject in subjectOneList"
          :key="subject.id"
          :label="subject.title"
          :value="subject.id"/>
      </el-select>
      <!-- 二级分类 -->
      <el-select v-model="courseInfo.subjectId" placeholder="二级分类">
        <el-option
          v-for="subject in subjectTwoList"
          :key="subject.id"
          :label="subject.title"
          :value="subject.id"/>
      </el-select>
    </el-form-item>
      <!-- 课程讲师 TODO -->
    <el-form-item label="课程讲师">
      <el-select
        v-model="courseInfo.teacherId"
        placeholder="请选择">
        <el-option
          v-for="teacher in teacherList"
          :key="teacher.id"
          :label="teacher.name"
          :value="teacher.id"/>
      </el-select>
    </el-form-item>

    <el-form-item label="总课时">
      <el-input-number :min="0" v-model="courseInfo.lessonNum" controls-position="right" placeholder=" "/>
  </el-form-item>
    <!-- 课程简介 TODO -->
    <el-form-item label="课程简介">
      <Tinymce :height="300" v-model="courseInfo.description"/>
    </el-form-item>
    <!-- 课程封面-->
    <el-form-item label="课程封面">
    <el-upload
      :show-file-list="false"
      :on-success="handleAvatarSuccess"
      :before-upload="beforeAvatarUpload"
      :action="BASE_API+'/eduoss/file'"
      class="avatar-uploader">
      <img :src="courseInfo.cover">
    </el-upload>

  </el-form-item>


    <el-form-item label="课程价格">
      <el-input-number :min="0" v-model="courseInfo.price" controls-position="right" placeholder=""></el-input-number>
    </el-form-item>
    <el-form-item>
      <el-button :disabled="saveBtnDisabled" type="primary" @click="saveOrUpdate">保存并下一步</el-button>
    </el-form-item>
  </el-form>


</div>
</template>

<script>

  import course from '@/api/course';
  import teacher from '@/api/teacher';
  import subject from '@/api/subject';
  import Tinymce from '@/components/Tinymce';

  export default {
    //申明组件
    components: { Tinymce },
    data(){
      return{
        saveBtnDisabled:false,

        courseInfo:{
          title: '',
          subjectId: '',
          subjectParentId: '',
          teacherId: '',
          lessonNum: 0,
          description: '',
          cover: '/static/267.png',
          price: 0
        },
        courseId: "",
        teacherList:[],
        subjectOneList:[],
        subjectTwoList:[],
        BASE_API: process.env.BASE_API // 接口API地址
      }
    },
    created() {
      //获取路由id值
      if(this.$route.params && this.$route.params.id){
        this.courseId = this.$route.params.id;
        this.getInfo();
      }else{
        this.getTeacherList();
        this.getOneSubject();
      }

    },

    methods: {
      //添加课程
      saveCourse(){
        course.addCourseInfo(this.courseInfo)
          .then(response => {
              //提示信息
              this.$message({
                type: 'success',
                message: '添加课程成功'
              });
            //跳转到第二步
            this.$router.push({path:'/course/chapter/'+response.data.courseId})
          })
      },
      //修改课程
      updateCourse(){
        course.updateCourseInfoById(this.courseInfo)
        .then(response =>{
          //提示
          this.$message({
            type: 'success',
            message: '添加课程成功'
          });
          //跳转到第二步
          this.$router.push({path:'/course/chapter/'+this.courseId})

        })
      },
      saveOrUpdate(){
        //判断添加还是修改
        if(!this.courseInfo.id){
          //添加
          //添加
          this.saveCourse();
        }else{
          this.updateCourse();
        }
      },

      //查询所有教师
      getTeacherList(){
        teacher.getListTeacher()
           .then(response => {
             this.teacherList = response.data.teachers;
           })
      },

      //所有的一级分类
      getOneSubject(){
        subject.getSubjectList()
        .then(response =>{
          this.subjectOneList = response.data.list;
        })
      },

      //二级联动
      subjectLevelOneChanged(value) {
        console.log(value);
        for (var i = 0; i < this.subjectOneList.length; i++) {
          //判断，所有一级分类id 和 点击一级分类id是否一样
          var oneSubject = this.subjectOneList[i];
          if (value === oneSubject.id) {
            this.subjectTwoList = oneSubject.children;
            //清空二级分类原始值
            this.courseInfo.subjectId = '';
            break;
          }
        }
      },

      //课程封面上传
      handleAvatarSuccess(res,file){
        console.log("封面上传成功");
        this.courseInfo.cover = res.data.url
      },
      beforeAvatarUpload(){
        const isJPG = file.type === 'image/jpeg'
        const isLt2M = file.size / 1024 / 1024 < 2
        if (!isJPG) {
          this.$message.error('上传头像图片只能是 JPG 格式!')
        }
        if (!isLt2M) {
          this.$message.error('上传头像图片大小不能超过 2MB!')
        }
        return isJPG && isLt2M
      },

      //根据课程id查询
      getInfo(){
        course.getCourseInfoId(this.courseId)
        .then(response =>{
          this.courseInfo = response.data.courseInfo;
          //查询出所有的分类
          subject.getSubjectList()
          .then(response =>{
            this.subjectOneList=response.data.list;
            for(var i=0; i<this.subjectOneList.length;i++){
              var oneSubject = this.subjectOneList[i];
              if(this.courseInfo.subjectParentId == oneSubject.id){
                this.subjectTwoList = oneSubject.children;
                break;
              }
            }
          })
          this.getTeacherList();
        })
      }


    }
  }
</script>
<style scoped>
  .tinymce-container {
    line-height: 29px;
  }
</style>
